Achilles Tendon, Injury and Treatment

Stuart Metcalfe FCPodS

Consultant Podiatric Surgeon

OB

JEC

TIV

ES 1 No one falls asleep

2 Review to physiology

3 Apply to clinical

Function

Connect muscle to bone

Transmission of force from

muscle to bone

> movement of the joint

Resist movement

Structure Overview

Tendon

Brilliant white

Fibro-elastic

Morphology

Collagen Content

•Type I - constitutes about 60% of the tendon and 95% of the total collagen

•Type III and V – make up the other 5%

Cellular

•90-95% tenoblasts/tenocytes

•5-10% chondrocytes/synovial cells/vascular cells

Blood Supply

Myo-tendinousjunction

Osteotendinous junction

Intrinsic

Paratenon

Synovial

Extrinsic

Innervation

BiomechanicsS

tress (

forc

e/a

rea)

Stress-strain curve showing basic physical properties of a tendon

Strain %

Response to exercise/immobility

Tis

sue Q

ualit

y

Loading State

Affect of Age

Types of Injury

• Inflammation of the tendonTendinitis

• Chronic disease state of tendon without inflammationTendinosis

• Tenosynovitis is inflammation of the tendon sheath.Tenosynovitis

• Inflammation of the paratenonParatenonitis

Pathophysiology

Healing Process

HEALING

remodelling phase

repairing phase

inflammatory phase

Achilles Tendon

Critical Zone

2–6 cm proximal to the calcaneal insertion, the tendons blood supply is diminished. This region of decreased vascularity is the usual region of Achilles rupture

Lagergren C, Lindholm A. Vascular distribution

in the Achilles tendon: an angiographic and microangiographic

study. Acta Chir Scand 1959;

116:491–495

Epidemiology - Achilles Tendinopathy

• Epidemiology

– Associated with running/jumping

– 6-18% all sporting injuries

– Average age 30-55 years

– Male predominence 6:1 ratio

– 30% are bi-lateral

– 41% of patients will go on to develop contra-lateral symptoms

To summarize; overuse injury to the Achilles tendon occurs at all ages, but more frequently in middle-aged

(30-55 years old) individuals, and is related to running and jumping with a high risk of bilateral injury.

Terminology

Classification of Achilles tendon injury

Pathology within

the sheath

Fibrosis + scarrring

Restricts gliding of the tendon

Can > or co-exist with tendinosis

Achilles

Tenosynovitis

Pathologicaldiagnosis

Concept(macroscopic pathology)

Histological appearance

Tendinosis Intratendinous degeneration(commonly caused by ageing, microtrauma andvascular compromise)

Collagen disorientation, disorganisation and fiber separation with an increase in cells andvascular space with or without neo-vascularisation and focal necrosis or calcification

Tendinitis/partialrupture

Symptomatic degenerationof the tendon with vasculardisruption and inflammatoryrepair response

Degenerative changes as noted above with superimposed evidence of tear, includingfibroblastic and myofibroblastic proliferation, haemorrhage and organising granulation tissue

Tendinitis/partialrupture

Inflammation of the outerlayer of the tendon(paratenon) alone,regardless of whether theparatenon is lined bysynovium

Mucoid degeneration in the areolar tissue is seen. A scattered mild mononuclear infiltrate with or without focal fibrin deposition and fibrinous exudate is also seen

Paratenonitiswithtendinosis

Paratenonitis associatedwith intratendinousdegeneration

Degenerative changes as noted for tendinosis with mucoid degeneration with or without fibrosis and scattered inflammatory cells in the paratenon alveolar tissue

No evidence inflammation

Tendon looses normal appearance

Microscopic evaluation : cell disorganisation,

degeneration, scarring

Achilles

Tendinosis

ACHILLES TENDINOSIS

• No pain with exercise

• Post exercise stiffness

• Local tenderness

Stage 1

• Pain during exercise

• No limitation to activity

• Stiffness post exercise >

• Local tenderness

Stage 2 • Pain with exercise

• < performance

• Prolonged pain / stiffness

• > tenderness

Stage 3

• Cannot exercise

• Prolonged stiffness

• ++ tenderness

Stage 4

Aetiology - Achilles Tendinopathy

Intrinsic factors Extrinsic factors

Age Environmental condition

Biomechanical Excessive loading

Decreased flexibility Footwear

Gender Training errors

Leg length discrepancy Side-effects of drug treatment

Muscle weakness / imbalance

Tendon blood supply

INTRINSIC EXTRINSIC PATHOLOGY

Pathogenesis – Achilles Tendinopathy

The overuse type of tendon injury

DIFFERENTIAL

DIAGNOSIS

Soleusmuscle Comp

syndrome

Os~T

Plantar fasciitis

PTTDS

Referred pain

Stress #

TTS

Peroneal

FHL / FDL

AT Rupture

Tumours

HISTORY

OBSERVATIO

N

Physical

EVALUATION

RISK PREVENTION FOOTWEAR COMPLIANCE

PRINCIPLES OF TREATMENT

RELATIVE REST

STRETCH

STRENGTHPHYSICAL THERAPY

STAGE 1 - TREATMENT

• Partial Rest

• Avoid risk factors

• Flexibility

• Eccentric strengthening

• Physical therapy

Treatment - Chronic

• In 90 of the 101 Achilles tendons (89%) with chronic painful mid-portion Achilles tendinosis, treatment was satisfactory and the patients were back on their pre-injury activity level after the 12-week training regimen

Quinolone

A/B’s

Ciprofloxacin

Tendon weakness

Pain

Cochrane

Imaging Suspected tendinopathy, ankle radiographs normal. Next study.

Radiologic ExamProcedure

AppropriatenessRating

Comments

MRI, ankle 9

US, ankle 6 Only if experienced examiner available

X-ray, ankle, stress films - with manual stressing

2

X-ray, ankle, stress films, - stress usingbiomechanical device

2

X-ray, ankle, stress films, - manual stress whileunder general anesthesia

2

NUC, bone scan 2

Conventional arthrography, ankle 2

CT arthrography, ankle 2

MR arthrography, ankle 2

Tenography, ankle 2

Diagnostic injection of anesthetic, ankle 2

Ap

pro

pria

ten

ess C

riteria

Scale

1 2

3 4

5 6

7 8

9

1 =

Least a

pp

rop

riate

9 =

Mo

st a

pp

rop

riate

Krebs Cycle/Pentose phosphate shunt/Glycolysis

Krebs cycle

Pentose phosphate shunt

Glycolysis

Achilles Tendon – Physical Examination

Medical history

•Diagnostic imaging

•Trauma

History of Present Illness

•When

•Where

•How

Social History

•Sport?

Medications

•NSAID’s

•Steroids

•?

Examination

•Pes planus/ pes cavus

•Calcaneal alignment varum or valgum

•Hallux valgum/ rigidis

•Leg length discrepancy/ pelvic rotation

•Strength testing

•ROM testing

Pain

•VAS Scale

•When

•Type

AGE’s

Non-vascular

connective tissue

Plasmproteins

Vascular Connective

tissue

LipoproteinsAmount of sugars

Exposure Glycation

Lysine residues

Hydroxylysine

LysylO

xid

ase

Grant et al 1997 > Density

> Cross-linking

> Stiffness

<

Elasticity

Increased stiffness of the Achilles